Swine study looks at mutating pig virus

WEST LAFAYETTE, Ind., Feb. 21 (UPI) -- U.S. scientists are conducting an investigation into the mutation of a pig virus that has developed into more deadly forms.

Research at the Indiana Animal Disease Diagnostic Laboratory on the Purdue University campus indicates the most recent mutation of a group of viruses called "porcine circoviruses" can cause widespread acute disease. Other pathogens can combine with the virus to significantly increase fatality rates.

In their effort to determine how the mutated form of porcine circovirus, or PCV2-1a, causes more deadly illness, the scientists focused on pigs exposed to a combination of PCV2 and bovine viral diarrhea virus.

"We think the new co-factors, including bovine viral diarrhea virus-like pathogen and other swine viruses, work together with porcine circovirus to attack the animals' systems and become more virulent," said Dr. Roman Pogranichniy, a Purdue veterinary virologist.

During the past decade porcine circoviruses have spread to nearly every area of the world but the mortality rate per herd is usually low. However, on farms also infected with other viruses, the mortality rate rose to 35 percent to 50 percent.

Porcine circoviruses don't infect people.

Purdue University and the National Pork Board are providing funding for the research.